Fork frame for an industrial truck

ABSTRACT

A detachable fork frame for an industrial lift truck is disclosed. The fork frame has two legs, each with a folding foot structure which allows it to stand freely when detached from the truck. The structure is designed for rapid mounting and demounting and is self storing.

United States Patent 1151 3,659,732

Downey 1 1 May 2, 1.972

[54] FORK FRAME FOR AN INDUSTRIAL 3,204,798 9/1965 Becker ..214/620 TRUCK 3,270,901 9/1966 3,415,339 12/1968 [72] Inventor: William P. Downey, Portland, Oreg. 3,455,476 7/1969 Assigm ijiiiii 211313 Brim 1 Filed! p 1969 2,756,884 7/1956 Senkowski et al. ...214/515 X 2,944,689 7/1960 Arnot ....214/620 [21] 852104 3,514,002 5/1970 Allegri et a1. ..214/621 [52] US. Cl ..214/62l, 214/515 I Primary Examiner-Robert .1. Spar [51] Int. Cl. ..B66f 9/12 A!t0meyFrancis Swanson [58] Field ofSearch ..214/620, 621, 515, 140

[57] ABSTRACT [56] References cued A detachable fork frame for an industrial lift truck is disn- STATES PATENTS closed. The fork frame has two legs, each with a folding foot structure which allows it to stand freely when detached from 2,394,458 2/1946 Lull ..214/62O UX the truck The Structure is designed f rapid mounting and 2,841,302 7/1958 Reisman et a1. ..214/621 demounting and is self storing. 2,906,405 9/1959 Erickson 3,090,494 5/1963 Thiele 214/620 X 8 Claims, 6 Drawing Figures Patented May 2, 1972 3,659,732

2 Sheets-Sheet l INVENTOR WILLIAM P. DOWNEY 1L; 3 BY Patented May 2, 1972 2 Sheets-Sheet z n mm MO V y W m w M m a L H L WY B FORK FRAME FOR AN INDUSTRIAL TRUCK BACKGROUND OF THE INVENTION 1 Field of the invention The present invention relates to industrial lift trucks and more particularly to the fork structure attached to the carriage of such lift trucks.

2. Description of the Prior Art The conventional fork structure of an industrial truck is unsuited for many types of cargo or materials. One example is the standardized container used in the transport industry. Such containers are usually rectangular structures 8 feet X 8 feet X 20 feet in size and have pockets on the top corners for picking them up. A top attaching device having mechanisms for engaging these attachments engaging these pockets is commonly employed when handling the containers. These attachments require a fork frame for mounting on the truck. The most serious drawback to such an arrangement is the problem of storage. When not in use, racks or other facilities must be provided for storing the container handler and the fork frame in an upright position so that when needed it may be easily attached to the truck.

SUMMARY OF THE INVENTION The container handler attachment described above forms no part of this invention and is cited only to illustrate a typical use for a fork frame. It should be clearly understood that this invention may be used for a variety of tasks and is not limited to the handling of containers.

In the present invention, the need for storage racks or special areas and facilities for storing frames is eliminated. The object of the invention is to provide a fork frame with legs and self-contained support structure by which it may be stored in any convenient place in an upright position without auxiliary racks or other devices.

A further object of this invention is to provide a fork frame which may be quickly attached or detached from the truck carriage without requiring special tools.

As a further object, means are provided for positively locking the fork frame to the carriage of the lift truck to prevent accidental detachment.

Other objects and advantages relating to the invention will become evident from the following detailed description which proceeds with reference to the accompanying drawings wherein:

FIG. 1 is a side elevational view of a lift truck having a fork frame mounted thereon in accordance with the invention;

FIG. 2 is a perspective view of the fork frame detached from the truck and standing in its self-supporting position;

FIG. 3 is a vertical sectional view taken along line 3-3 of FIG. 2;

FIG. 4 is an enlarged fragmentary perspective view of the locking means indicated by the capital letter A in FIG. 2;

FIG. 5 is an enlarged fragmented plan view of the strut members taken along line 5-5 of FIG. 2 and showing the details of the strut locking mechanism;

FIG. 6 is a sectional view of one of the legs showing the support mechanism in its stored position.

With reference to the drawings, FIG. 1 shows a lift truck 10 having a mast 10a and a load carriage 11 with the fork frame mounted thereon. A cargo container handler 12 and a cargo container 13 are shown in phantom. The fork frame consists of a horizontal member 14 which has two vertical support legs 16, one at each end. The horizontal member 14 has two holes 15 in its underside for receiving pins 1 1a which are on the carriage 11. Two forks 17 are welded to the horizontal member 14 and project at right angles to its longitudinal axis. The frame also carries an ear 18 used to shackle the fork frame to the container handler 12. Two rectangular lips 19 are joined at the comers formed by legs 16 and horizontal member 14. These elements define pockets to receive the carriage ll of the truck 10.

The legs 16 of the fork frame are anchored to the truck carriage I] by a locking means on each of them. Referring to FIG. 4, locking means A is comprised of a block 20, a levered pin 21. a pin latching plate 22, and a chain 23. These elements cooperatively mate with lock 24 on carriage 11.

Each of the support legs is hollow and open on the front face so as to allow storage of the folding support mechanisms within its body, as shown in FIG. 6. These folding support mechanisms provide free standing capability. Each such support mechanism consists of an upper strut member 25, lower strut member 26, and a ground engaging foot member 27. The upper member 25 is pivotally connected within the hollow vertical leg 16 with a pin 28, washers 29, and keepers 30. The lower strut member 26 is pivotally connected within the ground engaging foot member 27 with a pin 31, washers 32, and keepers 33. The ground engaging member is likewise pivotally connected to vertical support leg 16 with an identical pin, washer and keeper structure. Upper strut member 25 and lower strut member 26 are pivotally connected to one another via pin 34, washers 35, and keepers 36 to form a collapsible joint. Lower strut member 26 is narrower than and nests within upper strut member 25. Upper strut member 25 has a notch 37 which will allow the end of member 26 to swing through it when pivoted about pin 34.

A pair of holes 38a in upper strut member 25 match with a pair of holes 38b in member 26 to allow insertion of a locking toggle bolt 38. Insertion of toggle bolt 38 into holes 38a and 38b forms a single rigid member when the struts are positioned to provide free standing.

An car 39 is fastened to each vertical support leg 16. A second car 40 is mounted on the upper side of the ground engaging foot member 27. Slots 41 in the upper and lower strut members 25 and 26 and in the vertical leg 16 permit alignment and locking in the nested position when toggle bolt 38 is removed from holes 38a and 38b. In the nested position, toggle bolt 38 is inserted through ears 39 and 40 and locked in place.

OPERATION Attachment and detachment of the fork frame proceeds as follows: With the fork frame free standing, the operator approaches it from the rear and tilts the truck mast 10a forward and lowers the carriage 11 to a position slightly below lips 19 on the horizontal member 14 of the fork frame. This allows the carriage cross member to slip under lips 19 on the fork frame. As the carriage is raised, the cross member pins 11a engage holes 15 in horizontal frame member 14. Continued raising of the carriage 11 lifts the fork frame clear of the ground. Locking pin 21 is inserted into receiving block 24 on carriage 11 and rotated behind pin latching plate 22, locking the fork frame to the carriage l1. Toggle bolt 38 is removed from the folding strut members 25 and 26 enabling them to pivot to a nested position. The ground engaging member 27 can now be lifted upward and folded into leg 16. Ear 39 on legs 16 and ears 40 on ground support members 27 now align and the folding structure is locked by inserting toggle bolt 38, which was removed from struts 25 and 26, into the holes of ears 39 and 40. The fork frame is now ready for use.

To store the fork frame, the above steps are reversed. Toggle bolt 38 is removed from ears 39 and 40. The ground engaging members and struts are folded out of legs 16. Strut members 25 and 26 are locked together with toggle bolt 38. The fork frame is unlocked from carriage 11 by retracting pin 21. The fork frame is lowered to the ground. The mast 10a is tilted forward slightly and the carriage 11 lowered so that it clears lips 19. The driver can now back the truck away from the fork frame and the frame will stand by itself.

While embodiments of the present invention as herein disclosed, constitute a preferred form, it is to be understood that other forms might be adopted. Among these might be one wherein a single telescoping strut member is used. In another embodiment, the ground support member might be altered and strengthened so as to mount in cantilever without struts of any kind lclaim:

1. A load handling attachment for an industrial truck having a mast and carriage comprising:

A vertical fork frame detachably mounted on said carriage;

lifting means including at least one load engaging fork attached to the uppermost portion of said frame for handling said load;

and non-lifting means separate from said lifting means pivotable in a vertical plane with respect to said frame and attached to the lower most portion of said frame for supporting said frame in a substantially vertical position when said frame is detached from said carriage.

2. Apparatus according to claim 1 wherein said non-lifting means comprises a pair of elongate feet pivotally attached to said frame, said feet being selectively positionable in both a horizontal supporting and a vertical non-supporting position.

3. A materials handling attachment for an industrial truck having a mast and carriage comprising:

a lifting frame including a pair of downwardly depending legs;

said frame being detachably mounted on said carriage in a substantially vertical plane;

load handling means including at least one load engaging fork operatively connected to said frame,

ground engaging means attached to said frame including elongated ground engaging feet pivotable in a vertical plane and nestable within said legs for solely supporting said frame in a substantially upright position in cooperation with said legs when said frame is detached from said carriage;

and foot support means interposed between said ground engaging feet and said legs.

44 Apparatus according to claim 3 wherein said foot support means comprises;

a lower strut member pivotally connected to a ground engaging foot member;

an upper strut member downwardly depending leg;

means pivotally connecting said upper and lower strut members to each other;

and means locking said upper strut and said lower strut members together to form a single rigid member.

5. Apparatus according to claim 4 wherein said locking means comprises:

means defining a hole in said upper strut;

means defining a hole in said lower strut;

and a pin engagable with both of said holes simultaneously to lock said struts together.

6. A materials handling attachment for an industrial lift truck having a mast and carriage comprising;

a vertical fork frame detachably mounted on said carriage and having a horizontal member;

load lifting means including a pluralty of load engaging forks mounted on said horizontal member;

at least one vertical member depending downward from said horizontal member;

ground engaging means connected to the lower end of said vertical member for supporting said frame in a substantially upright position, when said frame is detached from said carriage;

and means for storing said ground engaging means within said vertical member when said frame is mounted on said carriage.

7. Apparatus according to claim 6 including means for attaching said frame to said carriage comprising:

a plurality of pockets in said horizontal member of said frame to receive said carriage and support said frame thereon.

8. Apparatus according to claim 6 wherein said downwardly depending vertical member comprises:

a hollow lower section open along one side constructed to receive and store said ground engaging means when said frame is mounted on said carriage.

pivotally connected to a 

1. A load handling attachment for an industrial truck having a mast and carriage comprising: A vertical fork frame detachably mounted on said carriage; lifting means including at least one load engaging fork attached to the uppermost portion of said frame for handling said load; and non-lifting means separate from said lifting means pivotable in a vertical plane with respect to said frame and attached to the lower most portion of said frame for supporting said frame in a substantially vertical position when said frame is detached from said carriage.
 2. Apparatus according to claim 1 wherein said non-lifting means comprises a pair of elongate feet pivotally attached to said frame, said feet being selectively positionable in both a horizontal supporting and a vertical non-supporting position.
 3. A materials handling attachment for an industrial truck having a mast and carriage comprising: a lifting frame including a pair of downwardly depending legs; said frame being detachably mounted on said carriage in a substantially vertical plane; load handling means including at least one load engaging fork operatively connected to said frame, ground engaging means attached to said frame including elongated ground engaging feet pivotable in a vertical plane and nestable within said legs for solely supporting said frame in a substantially upright position in cooperation with said legs when said frame is detached from said carriage; and foot support means interposed between said ground engaging feet and said legs.
 4. Apparatus according to claim 3 wherein said foot support means comprises; a lower strut member pivotally connected to a ground engaging foot member; an upper strut member pivotally connected to a downwardly depending leg; means pivotally connecting said upper and lower strut members to each other; and means locking said upper strut and said lower strut members together to form a single rigid member.
 5. Apparatus according to claim 4 wherein said locking means comprises: means defining a hole in said upper strut; means defining a hole in said lower strut; and a pin engagable with both of said holes simultaneously to lock said struts together.
 6. A materials handling attachment for an industrial lift truck having a mast and carriage comprising; a vertical fork frame detachably mounted on said carriage and having a horizontal member; load lifting means including a pluralty of load engaging forks mounted on said horizontal member; at least one vertical member depending downward from said horizontal member; ground engaging means connected to the lower end of said vertical member for supporting said frame in a substantially upright position, when said frame is detached from said carriage; and means for storing said Ground engaging means within said vertical member when said frame is mounted on said carriage.
 7. Apparatus according to claim 6 including means for attaching said frame to said carriage comprising: a plurality of pockets in said horizontal member of said frame to receive said carriage and support said frame thereon.
 8. Apparatus according to claim 6 wherein said downwardly depending vertical member comprises: a hollow lower section open along one side constructed to receive and store said ground engaging means when said frame is mounted on said carriage. 